Edward bo stock



' No. 67,487. PATLNTED AUG. 6, 1am.V

` L. BosTocK.

ADJUSTABLE PARALLEL RULBR.

EDWARD Bos'rocit, or ALBANY, NEW. YORK.' Letters Patent A70, 67,487,1latvd -'lu'fyzts 6. ISST.

IMPROVEMENT IN ADJUSTABLE PARALLELc RULERS.

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TO ALL WHOM IT MAY CONCERN: M

Beit known that I, EDWARD BOSTOCK, of the city of Albany, county of Albany', and State'of New York, have invented an Improved Adjustable Parallel Ruler; and I do hereby decla-re that the following, taken in connection with the drawings which accompany and form part of this specicatibn, is a description of my invention suilicent to enable those sklleod in the art to practise it.

This invention relates to an improvement in the construction oi` parallel rulers, 1and cons-ists in securing to l the ruler a rod or rods, uponwhich the gaugebar or holder may slide, and in securing adjustably to the holder P v a sliding, graduated gauge, having thereon a straight-edge parallel with the ruler, and against which the ruler shall rest when moved back for ruling a line parallel to thevone previously made. A parallel ruler embodying my invention is represented in the drawings, in whichi Figure 1 is a plan view of my ruler when closed.

Figure 2, the same when opened and its straight-edge adjusted for use; and

Figure 3, a cross-section taken in the line xx of fig. 2.

Like letters refer to like parts in the several figures.

A represents the ruler, having a. bevelled edge, if preferred, on the side H against which the pencil or other marking instrument bears when in the act of ruling a line. This edge may preferably have a graduated scale thereon, as shown. B is the gauge-holder, through which the rods or bars C passfso as `to allow ot' l adjustment for any required distance between the lines to be ruled. lhese rods are rigidly secured to the ruler A, or inserted'therein in any proper manner, and project beyond it sufficiently td equal the breadth of .bar B added to the longest distance that the bar may ever need to 4he moved back from the ruler. The outer ends of these rods'have removable heads G', knobs, or their equivalents, thereon,V to prevent bar B from sliding olif, as ,well as to limit its range of'motion and preseveits parallelism with the ruler when moved back to its extreme l limit. As in the present instance I have represented the rodsl as passing through holes drilled or bored through Ithe bari), I have cut notches, as shown at G, in the outer edge, to receivethese knobs. is an adjustable slide, witha graduatedv scale marked thereon, having, as part of the same, or rigidly secured thereto at right angles to its inner end, a long straight-edge, the object of which is to aiford a irm rest for the'edge M of the ruler when in contact with it, as hereinafter mentioned. |lhe scale on slide D ailords a ready means for adjustingl the edge of this slide at any desired distance from the edge M. K is a longitudinal slot, to admit of this adjustment, and E is a pin secured to B, and having a screw-thread therecn. L is a thumb-nut adapted for this pin, and which serves to secure the slidermly in any position to which it may be desired to adjust it,` l This slide is tightly steadied between the ways or plates I I. Instead oi'- two rods or bars, C, one only maybe used, if desired. In such case, it is to be placed centrally of the/length of the ruler, and so adapted as pot to .A interfere with the free action of the slide and its straight supporting-edge. The slide is preferably' made of metal, but I do not confine myself to any particular material or materials either for the ruler or the other parts. By unserewing or otherwise removing the knobs G', the ruler A may be withdrawn from B, and reversed, und the knobs replaced, so as to bring the bevelled edge H uppermost. It is then adapted for pencil ruling by draughtsmen and architects, and for other purposes where it is desirable to have a fiat' edge to rest on the material to be ruled, but when the bcvelled edge is beneath, as shown in fig. 3, the ruler is adapted for ruling with ink, or for ordinary purposes. For the purpose oi' its more convenient use when so reversed, I mark a graduated scale on both sides of the ruler. l, The oppation of my device when in use is as follows: Suppose the rule is to be set for ruling parallel lines u of one-fourth of an inch apart, (as shown in iig. 2.) This setting is eected by drawing luth B back on the rods as far as the knobsG will permit; next, by adjusting the straight-edge of slide te within one-fourth of an inch of edge hl, and then securing it tightly by the nut I new press theugers on the lathlB, then drawA back so that its rear edge M shall set closely against the straight-,edge or gauge 'of slide D. I now rule a line, and then presathe fingers on the lath A, and draw B back as far as the knobs or Lletents G G" will allow, then draw back A as before, and rule another line, and so on as far as'desired.

The simplicity ofthis device is evident: it has no complex parte, nor is it liable to derangement, while vany tendency of the ruler A to be dellected out of true parallelism with B, when the pressure of the lingers is if K uponB only, is met and corrected by the straight-edge of D.

aus? 2 o lf :un aware that parallel rulers have been made in ln'rhch the rnler was com'iectedwith a paralleli .bur o? 4 luth, and operated and steadiecl by n. complex system of tggledeffrs and motlbrolis. These .ldispense With.l

l That I claim as my invention Y f v l. y)She employment in paralel rulers of am adjustable slide, lhaving n. sti-aight supportngedge thereon, as and for thc purpose described. A l 2. In combina-tion n'itli snel] odjuetble straight ,supportingedgg 4one ork vmore guides or rods, as and for the purpose sot forth. I f Y' 3., In combination with sueh adjustable straight supporting-edge, one or more guides or rods, having knobs or heads thereon, ,as andffov tllepurpose s'et'forr.;h.' j lzw;v "l 1'" 'i 4. I claim such-.adiustable straight supporting-edge, When provided with a graduated scale thereon, as and fo'r the purpose set fort-h.

5. lhe combination of the'laths A and B witlrthe rods or bars C '0, for the purpose isebfoth.

6] The-combination of' 'the lavthsA-and B; rofl or`ro'ds Cyand the straightsupp-ortijrigdge, ag aridfor'the f 1,', .I ,'.1 :"I' 1, v l v 7. Providing the guide-'rods iv'ithremovable heads,to admit of reversing the ruler. `1e1a.`|.i'vel `y to a b'ar, B, so as to place its bevlelled edge against or awayffro'm 'the material to'beav ruled, for the 4purpose se'tforlth. v

. L EDWARD'BOSTOCK. Witnesses: ,l 

